Composition for the prevention and/or treatment of disorders due to abnormal lipid metabolism, comprising propionyl L-carnitine and chitosan

ABSTRACT

A composition is disclosed suitable for the prevention and/or treatment of disorders due to abnormal lipid metabolism, such as hypercholesterolaemia, atherosclerosis, hyperlipidaemia and obesity, and which can therefore take the form of a dietary supplement or of an actual medicine, comprising as characterizing active ingredients: (a) propionyl L-carnitine or a pharmacologically acceptable salt thereof, and (b) chitosan or its derivatives and congeners.

The present invention relates to a composition suitable for theprevention and/or treatment of disorders due to abnormal lipidmetabolism, such as hypercholesterolaemia, atherosclerosis,hyperlipidaemia and obesity, comprising as characterising activeingredients propionyl L-carnitine or a pharmacologically acceptable saltthereof, and chitosan or its derivatives and congeners.

Correspondingly, the composition may take the form and exert theactivity of a dietary supplement or of an actual medicine, dependingupon the support or preventive action or the strictly therapeutic actionwhich the composition is intended to exert according to the particularindividuals for whom it is to be used.

The action of the carnitines in general, and of propionyl L-carnitine inparticular, on lipid metabolism is well known, as is theiranti-atherosclerotic action and their action on lipid metabolismdisorders.

The carnitines activate the processes of β-oxidation ofintra-mitochondrial fatty acids and the oxidation of branched-chainamino acids, as well as regulating insulin activity. In particular,propionyl L-carnitine is capable of stabilising the phospholipidmembranes and the deformability of erythrocytes, as well as of acting onlipid peroxidation phenomena.

All these properties of the carnitines, and particularly of propionylL-carnitine, therefore emphasise their importance in the regulation ofthe metabolism of lipids and related phenomena such as atherosclerosis,hypercholesterolaemia, hypertriglyceridaemia, lipid accumulation andweight gain.

In the same sense, though with a different mechanism, a class ofsubstances known as chitosans may take effect on lipid metabolism. Thechitosans consist mainly of naturally occurring chitins of apolysaccharide type present above all in the exodermal part of shellfishin the form of poly-β-1,4-acetylglucosamine, the de-acetylation of whichcan lead to simpler structures such as poly-β-1,4-D-glucosamine, whichalso determine a greater solubility of the product related to the lowermolecular weight which may range from 100,000 to 1,000 according to theprocedure used for preparing the various oligomers.

The main characteristic of these products is related to theirlipophilicity and consists, via their basic charges, in binding to fattyacids, preventing their absorption, for instance, at the intestinallevel.

Experiments conducted in animals treated with chitosan have, in fact,demonstrated its efficacy in reducing hypercholesterolaemia, as well asserum and hepatic lipids, while experiments in human subjects havedemonstrated its efficacy particularly in diets suitable for reducingbody weight and in obese patients.

The lipid-lowering and weight-reducing effect of chitosan occurs fairlyrapidly, and no signs of intolerance or toxicity have been reported inthe course of its use.

It has now surprisingly been found that a composition containing as itscharacterising active ingredients:

-   -   (a) propionyl L-carnitine or a pharmacologically acceptable salt        thereof, and    -   (b) chitosan or its derivatives or congeners        is particularly useful, thanks to an unexpected, potent        synergistic action between the components, in the prevention        and/or treatment of disorders due to abnormal lipid metabolism,        such as hypercholesterolaemia, atherosclerosis, hyperlipidaemia        and obesity.

It has also been found that, advantageously, component (a) mayadditionally contain a “carnitine” selected from the group consisting ofacetyl L-carnitine, valeryl L-carnitine, isovaleryl L-carnitine andbutyryl L-carnitine or a pharmacologically acceptable salt thereof ormixtures thereof.

In the composition of the present invention, the weight ratio of (a) to(b) may range from 1:1 to 1:5, and preferably from 1:1 to 1:3.

The composition of the present invention may further comprise vitamins,coenzymes, mineral substances, amino acids and anti-oxidants.

The new composition, which is the object of the present invention,exploits the favourable activities exerted on lipid metabolism and onabsorption of fats by alkanoyl L-carnitines, and particularly propionylL-carnitine, or by propionyl L-carnitine together with acetylL-carnitine, valeryl L-carnitine, isovaleryl L-carnitine and/or butyrylL-carnitine, or a pharmacologically acceptable salt thereof, when theseare combined with chitosan or its congeners, achieving an unexpected andsurprising synergistic effect between its components which is extremelyadvantageous for exploitation in the field of the prevention andtreatment of disorders due to abnormal lipid metabolism, such ashypercholesterolaemia, atherosclerosis, hyperlipidaemia and obesity.

Experimental Atherosclerosis Tests

According to the regimen suggested by Malinow (Malinow M. R.,Atherosclerosis, 4:105, 1983) an atherogenic diet consisting of 24%casein, 10% cotton oil, 5% sodium chloride, 60% sugar, 1% cholesterol,and Vit. D₂ 200 mUST/g diet was administered for six weeks consecutivelyto different groups of male Wistar rats.

While one group of rats served as a control group, the other groups wereadministered chitosan (100 mg/kg) or propionyl L-carnitine (100 mg/kg)or chitosan (100 mg/kg) plus propionyl L-carnitine (100 mg/kg).

Another group of animals was administered acetyl L-carnitine (100 mg/kg)and butyryl L-carnitine (100 mg/kg) in addition to chitosan andpropionyl L-carnitine.

The results of these tests demonstrated a substantial protective effectagainst the atherosclerotic lesions induced by the atherogenic diet byboth propionyl L-carnitine and by chitosan, but surprisingly the maximumprotective effect was detectable when chitosan was combined withpropionyl L-carnitine.

In this group of rats, in fact, morphometric measurement of thethickness of the abdominal aorta and the intensity of the staininginduced by Sudan IV reveal a substantial synergistic action of theprotective effect afforded by the combination of the two components. Theprotection appears even more marked with the combination of the variousalkanoyl L-carnitines (propionyl L-carnitine, acetyl L-carnitine,butyryl L-carnitine) plus chitosan.

Tests in Experimentally Obese Rats

In these tests, male Wistar rats aged approximately two months wereadministered a lipogenic diet containing 50% glucose, 20% casein, 4%cellulose, 1% hazel nut oil, 18% starch, 2% vitamin mixture, and 5% saltmixture. The diet was administered for fifteen days consecutively todifferent groups of rats, one of which served as a control group,whereas the remaining groups were administered daily, per 100 g of diet,2 g of propionyl Lcarnitine or 1 g of chitosan, or the two compounds incombination at the same doses.

Another group was also administered acetyl L-carnitine (2 g/100 g diet)and butyryl L-carnitine (0.5 g/100 g diet) in addition to propionylL-carnitine and chitosan.

At the end of the fifteenth day since the beginning of the diet, feedconsumption and increase in body weight were calculated for each groupof rats. The results are presented in Tables 1 and 2 here below. TABLE 1Mean daily feed consumption (g)/animal Before At the end of treatmenttreatment Propionyl L-carnitine 19.8 ± 0.71 18.9 ± 0.50 Chitosan 18.5 ±0.45 16.6 ± 0.95 Propionyl L-carnitine + chitosan 19.3 ± 0.60 13.1 ±0.71 Propionyl L-carntine + acetyl 18.9 ± 0.55 12.5 ± 0.75 L-carnitine +butyryl L-carnitine + chitosan

TABLE 2 Mean body growth Final weight increase Controls 65.6 ± 4.1Propionyl L-carnitine 60.8 ± 5.2 Chitosan 49.5 ± 3.9 PropionylL-carnitine + chitosan 29.7 ± 2.9 Propionyl L-carnitine + acetyl 26.3 ±3.4 L-carnitine + butyryl L-carnitine + chitosan

On the basis of the data presented, there is a marked reduction in bodyweight together with a reduction in feed consumption, particularly inthe group of animals treated with propionyl L-carnitine plus chitosan,thus demonstrating in this case a true synergistic effect between thesetwo compounds.

Tests in Experimentally Hypercholesterolaemic Rabbits

Another type of experiment was conducted in New Zealand rabbits kept ona hypercholesterolaemic diet for forty days and treated with alkanoylL-carnitine, chitosan or with the two types of compounds in combination.In these tests, 0.5% by weight of cholesterol was added to the normaldiet of the rabbits consisting of 150 g/day and containing 2% fats, 20%fibres and 11% ashes.

While one group of animals was used as a control group, the remaininggroups were treated for six days with propionyl L-carnitine (2 g/100 gdiet), chitosan (1 g/100 g diet), or propionyl L-carnitine+acetylL-carnitine+butyryl L-carnitine (1 g+1 g+1 g/100 g diet) or withchitosan plus propionyl L-carnitine or chitosan plus the alkanoylcarnitine complex at the doses indicated above.

At the end of the fortieth day of treatment blood samples were takenfrom the ear vein from all animals and the plasma was used to calculatelipoprotein content in the various fractions (VLDL, LDL, HDL) afterultracentrifuging according to the method described by Noble (Noble R.P., J. Lipid Res., 9:693, 1968). The results of these tests, presentedin Table 3 here below, indicate that the increase in VLDL observed inthe control animals is much less significant in the animals treated withpropionyl L-carnitine, with alkanoyl L-carnitine or with chitosan, butthat it is completely inhibited in animals treated with the combinationof propionyl L-carnitine plus chitosan or with the alkanoyl carnitincombination plus chitosan.

These experiments, too, indicate the presence of a marked synergisticeffect between the alkanoyl L-carnitines and chitosan. TABLE 3 Plasmalipoprotein concentrations (mg/dl) after 40 days VLDL LDL HDL Day 0Controls 1.6 ± 1.1 10.6 ± 2.4  24.5 ± 3.7  Propionyl L-carnitine 1.4 ±0.9 9.8 ± 1.9 24.2 ± 2.4  Propionyl L-carnitine + acetyl 0.9 ± 1.8 12.4± 2.4  26.8 ± 3.1  L-carnitine + butyryl L-carnitine Chitosan 1.7 ± 1.426.9 ± 8.4  Chitosan + propionyl L-carnitine 1.1 ± 1.1 13.5 ± 3.5  25.4± 4.1  Chitosan + propionyl L-carnitine + acetyl 1.3 ± 0.9 10.5 ± 3.8 27.2 ± 3.5  L-carnitine + butyryl L-carnitine Day 40 Controls 1.132 ±305    445 ± 27.4 27.4 ± 11.5 Propionyl L-carnitine 832 ± 105  322 ±31.4 26.5 ± 10.4 Propionyl L-carnitine + acetyl 720 ± 205 309 ± 27  24.4± 11.2 L-carnitine + butyryl L-carnitine Chitosan 540 ± 55 209 ± 20   22 ± 12.2 Chitosan + propionyl L-carnitine 205 ± 19  180 ± 15   26 ±9.4 Chitosan + propionyl L-carnitine + acetyl  194 ± 12.4 195 ± 11  28.2± 9.1  L-carnitine + butyryl L-carnitine

Illustrative, non-limiting examples of compositions according to theinvention are reported hereinbelow. 1) Propionyl L-carnitine 300 mgChitosan (poli-β-1,4-N-acetyl-glucosamine) 300 mg 2) PropionylL-carnitine 100 mg Acetyl L-carnitine 100 mg Butyryl L-carnitine 100 mgChitosan (poli-β-1,4-N-acetyl-glucosamine) 300 mg 3) PropionylL-carnitine 600 mg Chitosan (poli-β-1,4-N-acetyl-glucosamine) 600 mg 4)Propionyl L-carnitine 200 mg Acetyl L-carnitine 200 mg ButyrylL-carnitine 200 mg Chitosan (poli-β-1,4-N-acetyl-glucosamine) 600 mg 5)Propionyl L-carnitine 500 mg Chitosan (poli-β-1,4-N-acetyl-glucosamine)500 mg 6) Propionyl L-carnitine 200 mg Acetyl L-carnitine 200 mg ButyrylL-carnitine 200 mg Chitosan (poli-β-1,4-N-acetyl-glucosamine) 600 mg 7)Propionyl L-carnitine 300 mg Chitosan (poli-β-1,4-N-acetyl-glucosamine)500 mg Vit. C 30 mg Zinc 1 mg Chromium 10 μg Vanadium 0.5 mg Seleniummethionine 30 μg 8) Propionyl L-carnitine 500 mg Chitosan(poli-β-1,4-N-acetyl-glucosamine) 500 mg Green tea catechin 50 mgPolyphenols of grapes 100 mg Resveratrol 1 mg Coenzime Q₁₀ 20 μg 9)Propionyl L-carnitine 300 mg Chitosan (poli-β-1,4-N-acetyl-glucosamine)500 mg Vit. C 100 mg Piridoxine 5 mg β-carotene 2 mg Taurine 100 mg Vit.PP 50 mg

What is meant by pharmacologically acceptable salt of L-carnitine oralkanoyl L-carnitine is any salt of these active ingredients with anacid that does not give rise to unwanted toxic or side effects. Suchsalts are well known to pharmacy experts.

Examples of suitable salts, though not exclusively these, are: chloride;bromide; iodide; aspartate, acid aspartate; citrate, acid citrate;tartrate; phosphate, acid phosphate; fumarate; acid fumarate;glycerophosphate; glucose phosphate; lactate; maleate, acid maleate;orotate; oxalate, acid oxalate; sulphate, acid sulphate,trichloroacetate, trifluoroacetate and methanesulphonate.

A list of FDA-approved pharmacologically acceptable salts is given inInt. J. of Pharm. 33, (1986), 201-217; this publication is incorporatedherein by reference.

1. A combination composition comprising as characterising activeingredients: (a) propionyl L-carnitine or a pharmacologically acceptablesalt thereof, and (b) chitosan or its derivatives and congeners.
 2. Thecomposition of claim 1, wherein the ingredient (a) further comprises atleast another carnitine selected from the group consisting of acetylL-carnitine, valery L-carnitine, isovaleryl L-carnitine and butyrylL-carnitine or their pharmacologically acceptable salts or mixturesthereof.
 3. The composition of claim 1, wherein the weight ratio (a):(b)is from 1:1 to 1:5.
 4. The composition of claim 1, wherein the weightratio (a):(b) is from 1:1 to 1:3.
 5. The composition of claim 1 whereinthe pharmacologically acceptable salt of L-carnitine or of itsderivatives is selected from the group consisting of: chloride; bromide;iodide; aspartate, acid aspartate; citrate, acid citrate; tartrate;phosphate, acid phosphate; fumarate, acid fumarate; glycerophosphate;glucose phosphate; lactate; maleate, acid maleate; orotate; oxalate;acid oxalate; sulphate acid sulphate; trichloroacetate; trifluoracetateand methane sulphonate.
 6. The composition of claim 1, which furthercomprises vitamins, coenzymes, mineral substances, aminoacids and/orantioxidants.
 7. The composition of claim 1, orally administrable, inthe form of a dietary supplement.
 8. The composition of claim 1,parenterally, rectally, sublingually or transdermally administrable, inthe form of a medicament.
 9. The dietary supplement of claim 7, for theprevention and/or treatment of disorders due to abnormal lipidmetabolism, hypercholesterolaemia, atherosclerosis, hyperlipidaemia andobesity.
 10. The medicament of claim 8 for the prevention and/ortreatment of disorders due to abnormal lipid metabolism,hypercholesterolaemia, atherosclerosis, hyperlipidaemia and obesity. 11.The dietary supplement of claim 9, in solid, semi-solid or liquid form.12. The medicament of claim 10, in solid, semi-solid or liquid form. 13.The dietary supplement of claim 11, in the form of tablets, lozenges,pills, capsules, granulates or syrups.
 14. The medicament of claim 12,in the form of tablets, lozenges, pills, capsules, granulates, syrups,vials or drops.
 15. A therapeutic method for the prevention and/ortreatment of disorders due to abnormal lipid metabolism,hypercholesterolaemia, atherosclerosis, hyperlipidaemia and obesitywhich comprises administering to a person in need thereof a combinationcomposition comprising the following ingredients: (a) propionylL-carnitine or a pharmacologically acceptable salt thereof, and (b)chitosan or its derivatives and congeners.